@InProceedings{norrish-slind05:tphols05,
  author =       {Michael Norrish and Konrad Slind},
  title =        {Proof Pearl: Using Combinators to Manipulate \texttt{let}-expressions in Proof},
  booktitle =    {Theorem Proving in Higher Order Logics, 18th International Conference},
  month =        {August},
  year =         2005,
  editor =       {Joe Hurd and Tom Melham},
  series =       {Lecture Notes in Computer Science},
  volume =       3603
  publisher =    {Springer-Verlag},
  pages =        397--408,
 }